Huang X, McGann JC, Liu BY, Hannoush RN, Lill JR, Pham V, Newton K, Kakunda M, Liu J, Yu C, Hymowitz SG, Hongo JA, Wynshaw-Boris A, Polakis P, Harland RM, Dixit VM. Phosphorylation of Dishevelled by protein kinase RIPK4 regulates Wnt signaling.
Science 2013;
339:1441-5. [PMID:
23371553 DOI:
10.1126/science.1232253]
[Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Receptor-interacting protein kinase 4 (RIPK4) is required for epidermal differentiation and is mutated in Bartsocas-Papas syndrome. RIPK4 binds to protein kinase C, but its signaling mechanisms are largely unknown. Ectopic RIPK4, but not catalytically inactive or Bartsocas-Papas RIPK4 mutants, induced accumulation of cytosolic β-catenin and a transcriptional program similar to that caused by Wnt3a. In Xenopus embryos, Ripk4 synergized with coexpressed Xwnt8, whereas Ripk4 morpholinos or catalytic inactive Ripk4 antagonized Wnt signaling. RIPK4 interacted constitutively with the adaptor protein DVL2 and, after Wnt3a stimulation, with the co-receptor LRP6. Phosphorylation of DVL2 by RIPK4 favored canonical Wnt signaling. Wnt-dependent growth of xenografted human tumor cells was suppressed by RIPK4 knockdown, suggesting that RIPK4 overexpression may contribute to the growth of certain tumor types.
Collapse